Permutation system of series circuit control



T. R. HENNIGAR ET AL Filed Oct. 20, 1948 0""0 INSULATION 2 NON CORUCTING s I I RETURN wmc FEED wmz PERMUTATION SYSTEM OF SERIES CIRCUITCONTROL Dec. 13,1949

Patented Dec. 13, 1949 PERMUTATION SYSTEM OF SERIES CIRCUIT CONTROLTheodore R. Hennigar, Chester Basin, and Harry B. MacKay, Mahone Bay,Nova Scotia, Canada Application October 20, 1948, Serial No. 55,564

3 Claims. 1

This invention relates to a permutation system of series circuitcontrol, and the object of the in vention is to provide a permutationsystem for any type of series circuit to make it impossible for anunauthorized person to close said circuit.

The invention broadly consists of a system embracing at least twocontact points in a series circuit of any type; a like number ofnormallyclosed self-closing cutout switches in said circuit; a keyhaving at least two current-conducting extensions adapted to contactsaid points simultaneously to close said circuit therethrough, andnormally dormant means intermediate said contact points and saidswitches adapted to be actuated to open one or both of said switcheswhen a key, having one or more extensions of greater reach than theextensions of said first-mentioned key, is used in an attempt to closesaid circuit.

In its preferred embodiment, the invention consists of a systemembodying a plurality of staggered contact points in a series circuit ofany type, each positioned in a channel longitudinally formed in asuitable panel; a like number of normally-closed self-closing cut-outswitches in said panel each reached through a channel in said circuit; aportable key having a like number of parallel key-rods of difierentextension or reach coupled together in pairs and adapted to be passedinto said channels to contact said contact points simultaneously toclose said circuit therethrough, and a normally dormant rod in each 01said channels, between said switches and said contact points, adapted tobe moved to open any of said switches when moved by a key having anextension of greater reach than said key-rods when an attempt is made toclose said circuit.

Fig. 1 is a schematic view showing, in section, an embodiment of thesystem for the control of a. door latch.

Fig. 2 is a plan of the inner end of the key.

In the drawings, like characters of reference refer to the same parts.

In its preferred form the invention comprises a plurality of key-rods 2,wired together in pairs in spaced relationship, as at 3. These rodsessentially reach or extend varying distances beyond a portable support4, therefore, which, together with said rods, is hereinafter referred toas the key. The said support 4, may be made of any suitablenon-conducting material so that the key rods 2 may be insulated fromeach other. If said-support is made of current-conducting material thekey rods 2 must be suitably insulated therefrom. A panel 5 preferablymade of any suitable insulating material, is provided with as 2 manyparallel channels 6 as there are key-rods 2. These channels are spacedat distance apart equal to the distance separating said key-rods, andare to open at one end through the same side of the panel. Contactpoints 1 are located with respect to said channels 6, so that when thekey-rods 2 are passed thereinto they will make contact with said contactpoints. The location of said contact points in said channels and theindividual length or reach of the key-rods 2, is such that said key-rodssimultaneously make contact therewith when they have been fully insertedinto said channels.

Slideable in said channels 6 are normally-dormant non-current-conductingrods 8, normally out of contact with the key-rods 2. Each channel opensinto a pocket 9 in said panel, and in each pocket are two terminals, I!)and H. Fastened to each terminal H, is a spring-key l2, which normallypresses against its associated ter minal In. These spring-keys I2, andterminals l0 and H, are hereinafter referred to as cut-out switches.

Bearing in mind that at least two key-rods must simultaneously contacttwo contact points 1 to close the circuit, if attempt should be made touse a key in which any key-rod reaches up into a channel 6 far enough tocontact the associated rod 8 thereof, it will move this rod to move thekey l2 out of contact with its terminal [0, thus opening the circuitbefore the contact points I can be simultaneously contacted by all ofits key-rods. Thus it will be seen that keys can be made usable withcertainty only in a given panel, and hence a very wide range of keys andpanels can be made. As before mentioned, the drawing shows the systemadapted to be used to control the latch or bolt of a door. When thecurrent is closed solenoid I3 is magnetized and withdraws the bolt orlatch M from the outer dotted position into the inner dotted position,thus unlocking the door l5. When the key is removed from the panel, thecircuit is opened, and the solenoid demagnetlzed, thus permitting thespring "5 to return the bolt or latch I4 in position to lock the doorwhen it is shut.

The current enters through the feed-wire a to the terminal I I, throughthe key l2 to the terminal l0, through the wire b, through similarterminals and keys into the 'wire 0, and on through like wires andterminals and keys clearly shown to the contact point 1 at theright-hand side of the panel and continues on through the key-rods 2 andwires 3 to the contact points I wired together in the middle of saidchannel and finally out from 3 the contact point i at the left-hand sideof the panel, through the wire 11, and by way of the solenoid [3 intothe return wire e, thus completing the circuit.

Even if only two contact points 1 are used, the distance of same withinthe channels 6 may be the same, and two key-rods of equal reach usedtherewith may contact said :points simultaneously. A very wide range ofpermutations can be obtained with the elements just mentioned, incombination with rods 8, but obviously a very much wider range ofpermutations can be obtained where a greater number of pairs of key-rods2 and contact points i are used.

The principle of the invention may-be embodied,

points in said circuit; a key having at least two current-conductingextensions adapted to .con- .tact said contact points simultaneously toclose said circuit; two normally-closed cut-out switches in saidcircuit, and normally dormant means in termediate said contact pointsand'said switches adapted to .be actuated to open one .or both of saidcut-out switches when another key, having one or more extension ofgreater reach thanrthe extensionsof said first-mentioned key --is usedin an attempt to close said circuit.

2. A permutation system of series circuit control comprising a circuit;at least two contact points in staggeredrelations in said circuit; akeyhaving at least twocurrent-conducting extensions of diiierent reachesadaptedto contact said contact points simultaneously to close saidcircuit;

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4 two normally-closed cut-out switches in said circuit, and normallydormant means intermediate said contact points and said switches adaptedto be actuated to open one or both of said cut-out switches when anotherkey, having one or more extensions of greater reach than the extensionsof said first-mentioned key is used in an attempt toclose said circuit.

3. In a permutation system circuit control a panel, made of suitableinsulating material, provided with a plurality of parallel channels eachopening at one end through the same side of the panel; a plurality ofnormally-closed cut-out switches housed in said panel and eachaccessible from a channel; a contact point in each channel "in"staggered position in relation to its fellows accessible from the openend thereof; a common "series circuit for said switches and contactpoints;

- nally movable in each of said channels and nor- REFERENCES CITED Thefollowing vreferences are of record in the file of this patent:

UNITED STATES PATENTS Name vDate Leschke et a1 Apr. 25, 1933 Number 11,905,965

